Sun Cluster Geographic Edition Data Replication Guide for EMC Symmetrix Remote Data Facility

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Administering EMC Symmetrix Remote Data Facility Data Replication Device Groups

This section provides the following information about administering EMC Symmetrix Remote Data Facility data replication device groups:

For details about configuring a EMC Symmetrix Remote Data Facility data replication protection group, see How to Create and Configure an EMC Symmetrix Remote Data Facility Protection Group.

How to Add a Data Replication Device Group to an EMC Symmetrix Remote Data Facility Protection Group

Log in to a cluster node.

You must be assigned the Geo Management RBAC rights profile to complete this procedure. For more information about RBAC, see Sun Cluster Geographic Edition Software and RBAC in Sun Cluster Geographic Edition System Administration Guide.

Create a data replication device group in the protection group.

This command adds a device group to a protection group on the local cluster and propagates the new configuration to the partner cluster if the partner cluster contains a protection group of the same name.
# geopg add-device-group -p property [-p...] devicegroupname protectiongroupname
-p property
Specifies the properties of the data replication device group.

You can specify the following EMC Symmetrix Remote Data Facility properties:
- DG_or_CG – Specifies that the device group is an EMC Symmetrix Remote Data Facility device group.
  
  You must set this property to DG.
- R1SID – Specifies the primary (RDF1) EMC Symmetrix ID of the EMC Symmetrix devices.
  
  The data replication layer automatically sets the value of this property. You should specify the primary (RDF1) EMC Symmetrix ID of the EMC Symmetrix devices if you change the settings of the EMC Symmetrix host.
- R2SID – Specifies the secondary (RDF2) EMC Symmetrix ID of the EMC Symmetrix devices.
  
  The data replication layer automatically sets the value of this property. You should specify the secondary (RDF2) EMC Symmetrix ID of the EMC Symmetrix devices if you change the settings of the EMC Symmetrix host.
devicegroupname

Specifies the name of the new data replication device group.

protectiongroupname

Specifies the name of the protection group that will contain the new data replication device group.
For information about the names and values that are supported by Sun Cluster Geographic Edition software, see Appendix B, Legal Names and Values of Sun Cluster Geographic Edition Entities, in Sun Cluster Geographic Edition System Administration Guide.

For more information about the geopg command, refer to the geopg(1M) man page.

Example 2–10 Adding a Data Replication Device Group to an EMC Symmetrix Remote Data Facility Protection Group

This example adds the EMC Symmetrix Remote Data Facility data replication device group to the srdfpg protection group.

# geopg add-device-group devgroup1 srdfpg

Validations Made by the Data Replication Subsystem

When the EMC Symmetrix Remote Data Facility device group is added to a protection group, the data replication layer makes the following validations.

The specified device group name exists in the EMC Symmetrix Remote Data Facility configuration.
The replication role matches the EMC Symmetrix Remote Data Facility protection group role.
The EMC Symmetrix source, R1SID, and the EMC Symmetrix target, R2SID, can be reached.

When an EMC Symmetrix Remote Data Facility device group is added to a protection group, a Sun Cluster data replication resource is automatically created by this command. This resource monitors data replication state. The name of the resource is sc_ggeo_dr-SRDFprotectiongroupname-devicegroupname. This resource is placed in the corresponding Sun Cluster resource group, which is named sc_geo_dr-SRDFprotectiongroupname.

Caution –

Do not change, remove, or bring offline these resources or resource groups. Use only Sun Cluster Geographic Edition commands to administer replication resource groups and resources that are internal entities managed by Sun Cluster Geographic Edition software. Altering the configuration or state of these entities directly with Sun Cluster commands could result in unrecoverable failure.

How the State of the EMC Symmetrix Remote Data Facility Device Group Is Validated

The state of each EMC Symmetrix Remote Data Facility device group is mapped to the Sun Cluster Geographic Edition resource group state. The symrdf -g dgname query command returns this state.

The remainder of this section describes the individual device group states and how these states are validated against the local role of the protection group.

Determining the State of an Individual EMC Symmetrix Remote Data Facility Device Group

An individual EMC Symmetrix Remote Data Facility device group can be in one of the following states:

Synchronized
SynInProg
Failedover
R1 Updated
R1 UpdInProg
Split
Suspended
Partitioned
Invalid

Determining the Aggregate EMC Symmetrix Remote Data Facility Device Group State

If a protection group contains only one EMC Symmetrix Remote Data Facility device group, then the aggregate device group state is the same as the individual device group state.

When a protection group contains multiple EMC Symmetrix Remote Data Facility device groups, the aggregate device group state is obtained as described in the following table.

Table 2–1 Conditions That Determine the Aggregate Device Group State


Condition	Aggregate Device Group State
Any of the individual device group states are `Invalid`.	`Invalid`
Any of the individual device groups states are `Partitioned` and none of the individual device group states is `Invalid`.	`Partitioned`
One or more of the individual device groups states are `Suspended` and none of the individual device group states is `Invalid`, or `Partitioned`.	`Suspended`
One or more of the individual device groups states are `Split` and none of the individual device group states is `Invalid`, `Partitioned`, or `Suspended`.	`Split`
One or more of the individual device groups states are `R1 UpdInProg` and none of the individual device group states is `Invalid`, `Partitioned`, `Suspended`, or `Split`.	`R1 UpdInProg`
One or more of the individual device groups states are `R1 Updated` and none of the individual device group states is `Invalid`, `Partitioned`, `Suspended`, `Split`, or `R1 UpdInProg`.	`R1 Updated`
One or more of the individual device groups states are `Failedover` and none of the individual device group states is `Invalid`, `Partitioned`, `Suspended`, `Split`, `R1 UpdInProg`, or `R1 Updated`.	`Failedover`
One or more of the individual device groups states are `SynInProg` and none of the individual device group states is `Invalid`, `Partitioned`, `Suspended`, `Split`, `R1 UpdInProg`, `R1 Updated`, or `Failedover`.	`SynInProg`
All of the individual device group states are `Synchronized`.	`Synchronized`

Determining the EMC Symmetrix Remote Data Facility Pair State

The resource status message reflects the role and state of the RDF pair. For example, the resource status and status message of Faulted Split, is reported when the RDF pair is in a Split state.

The RDF pair state is mapped to the associated resource status as described in the following table.

Table 2–2 Mapping From the RDF Pair State to the Resource Status


Condition	Resource Status	Status Message
The RDF pair state is `Invalid` and the pair state is not `Incorrect Role`.	`Faulted`	`Invalid state`
The RDF pair state is `Partitioned` and the pair state is not `Incorrect Role`, or `Invalid`.	`Faulted`	`Partitioned`
The RDF pair state is `Suspended` and the pair state is not `Incorrect Role`, `Invalid`, or `Partitioned`.	`Faulted`	`Suspended`
The RDF pair state is `SyncInProg` and the pair state is not `Incorrect Role`, `Invalid`, `Partitioned`, or `Suspended`.	`Degraded`	`SyncInProg`
The RDF pair state is `R1 UpdInProg` and the pair state is not `Incorrect Role`, `Invalid`, `Partitioned`, `Suspended`, or `SyncInProg`.	`Faulted`	`R1 UpdInProg`
The RDF pair state is `Split` and the pair state is not `Incorrect Role`, `Invalid`, `Partitioned`, `Suspended`,`SyncInProg`, or `R1 UpdInProg`.	`Faulted`	`Split`
The RDF pair state is `Failed over` and the pair state is not `Incorrect Role`, `Invalid`, `Partitioned`, `Suspended`,`SyncInProg`, `R1 UpdInProg`, or `Split`.	`Faulted`	`Failed over`
The RDF pair state is `R1 Updated` and the pair state is not `Incorrect Role`, `Invalid`, `Partitioned`, `Suspended`,`SyncInProg`, `R1 UpdInProg`, `Split`, or `Failed over`.	`Faulted`	`Replicating with role change`
The RDF pair state is `Synchronized`.	`Online`	`Replicating`

The state of the RDF pair determines the availability of consistent data in the partnership. When the state of the RDF resource on the primary or secondary cluster is Degraded or Faulted, the data volumes might not be synchronized even if the application can still write data from the primary volume to the secondary volume. The RDF pair will be in a Partitioned state and the invalid entries will be logged as the data is written to the primary volume. Manual recovery operations are required to resolve the error and resynchronize the data.

How to Modify an EMC Symmetrix Remote Data Facility Data Replication Device Group

Log in to a cluster node.

You must be assigned the Geo Management RBAC rights profile to complete this procedure. For more information about RBAC, see Sun Cluster Geographic Edition Software and RBAC in Sun Cluster Geographic Edition System Administration Guide.

Modify the device group.

This command modifies the properties of a device group in a protection group on the local cluster. Then the command propagates the new configuration to the partner cluster if the partner cluster contains a protection group of the same name.
# geopg modify-device-group -p property [-p...] srdfdevicegroupname protectiongroupname
-p property

Specifies the properties of the data replication device group.

For more information about the properties you can set, see Appendix A, Standard Sun Cluster Geographic Edition Properties, in Sun Cluster Geographic Edition System Administration Guide.

srdfdevicegroupname

Specifies the name of the new data replication device group.

protectiongroupname

Specifies the name of the protection group that will contain the new data replication device group.

Example 2–11 Modifying the Properties of an EMC Symmetrix Remote Data Facility Data Replication Device Group

This example modifies the R1SID property of a data replication device group that is part of an EMC Symmetrix Remote Data Facility protection group.

# geopg modify-device-group -p R1SID=215 srdfdg srdfpg

How to Delete a Data Replication Device Group From an EMC Symmetrix Remote Data Facility Protection Group

Before You Begin

You might delete a data replication device group from a protection group if you added a data replication device group to a protection group. Normally, after an application is configured to write to a set of disks, you would not change the disks.

Deleting a data replication device group does not stop replication or change the replication status of the data replication device group.

For information about deleting protection groups, refer to How to Delete an EMC Symmetrix Remote Data Facility Protection Group. For information about deleting application resource groups from a protection group, refer to How to Delete an Application Resource Group From an EMC Symmetrix Remote Data Facility Protection Group.

Log in to a cluster node.

You must be assigned the Geo Management RBAC rights profile to complete this procedure. For more information about RBAC, see Sun Cluster Geographic Edition Software and RBAC in Sun Cluster Geographic Edition System Administration Guide.

Remove the device group.

This command removes a device group from a protection group on the local cluster. Then the command propagates the new configuration to the partner cluster if the partner cluster contains a protection group of the same name.
# geopg remove-device-group devicegroupname protectiongroupname
devicegroupname

Specifies the name of the data replication device group

protectiongroupname

Specifies the name of the protection group

When a device group is deleted from an EMC Symmetrix Remote Data Facility protection group, the corresponding Sun Cluster resource, sc_geo_dr-SRDF-protectiongroupname-devicegroupname, is removed from the replication resource group. As a result, the deleted device group is no longer monitored. The replication resource group is removed when the protection group is deleted.

Example 2–12 Deleting a Replication Device Group From an EMC Symmetrix Remote Data Facility Protection Group

This example removes an EMC Symmetrix Remote Data Facility data replication device group srdfdg from the srdfpg protection group.

# geopg remove-device-group srdfdg srdfpg